“This is interesting!” Merry softly exclaimed. “Yes, very!” grunted Browning. “Give something to know what it means. Can you tell?” “No,” confessed Frank. “All I could make out is that three of those fellows are making a fourth lead them somewhere.” “Let’s follow,” suggested Diamond. “Let’s know what they are up to. What do you say, Merry?” “Just what I’d like to do.” “What’s the use----” began Rattleton. Then he checked himself, biting his tongue and thinking: “Don’t be a fool! If you’re scared, don’t give it away. They may never know it.” “Come ahead!” Frank arose and took the lead. The others trailed out after him. He was following the sailors through the darkness, and his companions were following him. Not one of them knew what the adventure might lead to; all of them realized that it might be very dangerous. They were sure the men ahead were desperate ruffians, but curiosity overcame every other emotion. CHAPTER VI. GHOSTLY SOUNDS. Clank! clink! clank! “What are they doing?” “Digging!” The boys had followed the men to a lonely part of the island, where the wind howled through the trees when it came down in fitful gusts, or moaned when it sank low. The booming of the surf was like the steady roar of a distant battery in action. The night seemed full of alarms and terrors. Frank had followed the unknown men with the skill of an Indian trailer. The others had followed him with less skill, but the sounds of the storm had favored them by drowning such noises as they made while stumbling along through the darkness. At last the men had stopped, and, bit by bit, the boys had crept upon them. There was a gleam of light to guide them. The lights came from two dark lanterns, the sides of which had been opened. The lanterns were held to aid the men who were at work. Clink-clank! clink-clank! clink-clank! One man was plying a pick. After a little he paused. Scrape-swish! scrape-swish! Another man was using a spade, flinging out the earth which the man with the pick had loosened. “Digging!” repeated Diamond, in a palpitating whisper. “What does that mean?” “Digging!” fluttered Rattleton. “Digging a grave!” “Huah!” grunted Browning. “For whom?” “Somebody! I knew it! Going to bury that girl! She’s been kidnaped! They’re going to put her out of the way!” “How about the man they have with them--the man they forced to show them this spot?” asked Diamond. “What are they going to do with him?” “Don’t know. Kill him, too, perhaps! Let’s git!” “And leave him to be killed?” said Frank. “Well, I didn’t think that of you, Harry!” Harry felt the cut of the reproach. He choked as he tried to whisper something back. After a little, he asked: “Well, what can we do? Tell me that.” “We can do our best for the man, if necessary; but I do not think it will be necessary.” “Then you think--just what?” “That you are off your trolley.” “How? Which way?” “I do not believe they are digging a grave.”